1. Technical Field
This device relates to rotators for backhoe attachments such as power shears and the like that are positioned on the end of backhoe booms. Such rotators are used to move the attachment about a center axis defined by the rotator which is pivotally disposed on the boom for vertical movement.
2. Description of Prior Art
Prior Art devices of this type have been dedicated to one type of attachment on a rotary mount in a specific area of expertise, see for example U.S. Pat. Nos. 4,451,194, 4,017,114 and U.S. Pat. No. 3,920,137.
In U.S. Pat. No. 4,451,194 an integral heel tree length grapple can be seen for lifting and maneuvering elongated items in grapple jaws extending from an elongated arm both of which are pivotally secured to a frame on the end of a boom. The hydraulic motor drives a sproket gear attached to the elongated frame pivoting same in an arcuate path about a pivot point for a limited effective rotational movement.
U.S. Pat. No. 4,017,114 is directed to a multi-directional grapple that attaches to the end of a backhoe boom. The dedicated grapple assembly can be rotated about a central axis on a mounting plate by a hydraulic motor and gear assembly.
In U.S. Pat. No. 3,920,137 an excavating machine with clam shell bucket can be seen that uses multiple pivot points to achieve multi-directional positioning of the bucket in relation to the boom on which it is attached.